The goal of this career development plan is to launch an independent research career in children's environmental health, with a particular focus on environmental toxicants and child neurobehavioral development. Some industrial chemicals, most notably lead and methylmercury (CH3Hg), are recognized causes of neurodevelopmental disorders and subclinical brain dysfunction. The developing fetus and young children are particularly susceptible to environmental insults, but investigations of the effects of prenatal and early childhood exposure to most chemicals are limited. This career development plan will build on the candidate's formal training in epidemiology to obtain the background in environmental toxicology needed to develop hypotheses and design environmental neuroepidemiology studies that are well-grounded in biological mechanisms of toxicity. This plan incorporates didactic training in environmental toxicology and molecular epidemiology, practical training in the use of biomarkers of exposure and neurobehavioral assessments in epidemiologic research, and additional training in complex statistical techniques. The research component builds on the Study of C8 and Neurobehavioral Development, an ongoing study of 550 children in a region of the Mid-Ohio Valley subjected to perfluorooctanoic acid and other industrial pollutants. The knowledge, skills, and experience gained through the training portion of this career development plan will be applied to examine the associations of biomarkers of exposure to perfluorinated compounds, manganese, and arsenic with child neurobehavioral development at ages 6 to 11. The candidate is an Instructor in the Department of Preventive Medicine at Mount Sinai School of Medicine, a nationally and internationally recognized center of excellence in preventive medicine, occupational and environmental medicine, community health, and environmental pediatrics. An interdisciplinary mentorship team has been selected to provide guidance and expertise in environmental toxicology, environmental epidemiology, and child neurobehavioral development. Fulfillment of this career development plan will enable the candidate to critically appraise the state of knowledge on environmental toxicants, to recognize the most promising substantive directions for future research, to select contextually appropriate markers of exposure and outcome, and ultimately to identify populations especially vulnerable to environmental toxicants. The proposed training and research program will position the candidate to work effectively with a number of active, multidisciplinary groups at the completion of the award period. Moreover, this career development plan will facilitate the candidate becoming, in time, a leading expert and independent investigator in children's environmental health.